Certain embodiments of the present invention generally relate to a latch, and more particularly to a latch for a ground shield that encloses an electrical connector.
Connectors are known for interconnecting various electrical media, components, and structures such as printed circuit boards (PCBs), coaxial cables, discrete circuit components, flex circuits and the like. The connectors may interconnect signal and/or power lines between two similar or different media, components and structures, such as between a flex circuit and a PCB, between two PCBs and the like. An example of an interconnection between two PCBs is a board-to-board connector. Connectors are offered in a variety of shapes and sizes, depending upon several competing criteria.
Typically, connectors include a connector interface and an interface with another media, component or structure (hereafter, generally a xe2x80x9ccircuit interfacexe2x80x9d). The circuit interface may include signal and ground contacts, or pins, that may be retained within receptacles formed in a circuit board, flex circuit and the like. The connector interface may also include signal and ground contacts. The connector interface of one connector typically mates with a connector interface of another connector, which, in turn, may be connected to a different printed circuit board, flex circuit or the like. Thus, the mating of connectors provides a path over which high-speed data signals from one circuit may travel to and from another circuit.
In many applications, it is desirable to protect electrical components of systems surrounding or proximate the electrical connectors, and to protect the quality of signals passing from one circuit to another. At least limited signal and component protection has been afforded by covering connectors with a ground shield of suitable stock material. Typically, a ground shield covers portions of a connector that do not interface with other connectors or other circuits. A typical ground shield includes a latching mechanism that securely latches the ground shield around the connector.
Typical latching mechanisms include a latch insert portion and a receptacle portion. The receptacle portion receives a latching protrusion located on the latch insert portion. The latching protrusion is biased into the receptacle portion thereby securing or engaging the latch. The latch is held engaged by a constant external force applied to the latch from below the latch protrusion. That is, the latch typically requires a directional force exerted by an external structure, such as a housing of the electrical connector or a spring member on the latch, to ensure that the latch remains engaged. Without directional forces exerted by the supporting structure positioned underneath the latch, or by the latch itself (for example, a spring member), the latch would disengage due to the fact that there is no force biasing the latch projection of the latch insert portion into the latch receptacle portion. Further, even when directional forces are exerted by supporting structure, such as an electrical connector, the latch may disengage if the connector housing warps, expands or shrinks. Also, the connector housing may have irregular and/or non-uniform surfaces that exert an uneven, non-uniform normal force on the latch. Consequently, the latch may disengage due to the non-uniform force exerted upon it.
Thus a need exists for a more robust latch that secures a ground shield over an electrical connector. Also, a need exists for a ground shield latch that remains engaged without external directional forces being exerted by supporting structure positioned underneath the latch.
In accordance with certain embodiments of the present invention, a latch assembly for latching a ground shield has been developed. The latch assembly latches together ends of the ground shield. The ground shield covers an electrical connector. The latch assembly comprises a latch receptacle portion and a latch insert portion. The latch receptacle portion includes a receptacle main body arranged in a first plane and a strap arranged in a second plane that differs from the first plane. The strap is spaced apart from the receptacle main body to define a slot therebetween. The latch receptacle portion also includes a clearance bridge and a window provided in the receptacle main body. The clearance bridge is formed between the strap, which is formed at the edge of the ground shield, and the window. That is, the clearance bridge separates the strap from the window.
The latch insert portion includes an insert main body and a tongue with a latching projection formed on, and extending from, one side of the tongue. The tongue is offset from a plane containing the insert main body. When the latch receptacle portion and latch insert portion are joined, the strap exerts a normal force on the tongue biasing the latching projection into the window. In order to latch the latch insert portion and the latch receptacle portion together, the tongue is inserted into the slot and the tongue and/or the strap is deflected as the tongue traverses the clearance bridge toward said window. When the latch assembly is fully engaged, that is, fully latched, the receptacle main body and the insert main body are coplanar. Also, when fully engaged, the strap and the receptacle main body sandwich the tongue therebetween.
In certain embodiments of the present invention, the latch receptacle portion and the latch insert portion are formed integrally from a common piece of stock material. The latch receptacle portion may be stamped from one end of the stock material and the latch insert portion may be stamped on a second end of the stock material.
Certain embodiments of the present invention also provide a method of manufacturing a ground shield for an electrical connector. The method comprises the steps of first stamping a latch receptacle portion, having a receptacle main body and a strap, from a first end of a ground shield second stamping a latch insert portion, having an insert main body and a tongue extending from the insert main body, from a second end of the ground shield forming a latching projection extending outward from the tongue and offsetting a strap from the latch receptacle portion to form a slot between the window in the main body of the latch receptacle portion. The method also comprises folding the ground shield over an electrical connector, sandwiching the tongue between the strap and the receptacle main body, latching the latch insert portion and the latch receptacle portion together such that the insert main body is coplanar with the receptacle main body. The method also comprises fully engaging the latch receptacle portion with the latch insert portion by inserting the tongue into the slot; exerting a normal force on the tongue with the strap; and biasing the tongue into an engaged position with the receptacle main body.
Thus certain embodiments of the present invention provide a more robust latch that may be used to secure a ground shield over an electrical connector. Also, certain embodiments of the present invention provide a ground shield latch that remains engaged even without external supporting structure, such as an electrical connector, positioned underneath the latch.